I rather depends on what you're recording, and 'essential' is really a relative term. If you're recording your singing voice, the Shure will do the job. If you're wanting to record other instruments, such as acoustic guitar, or even your bass amp, the Shure will work, but with far less fidelity.
In general, the SM58 is an excellent stage vocal mic, as it's robust, and all sound engineers know exactly how it will perform. For studio (including home studio...) stuff, a large-diaphragm condenser mic is the standard 'go-to' mic for best recording quality in most situations. You've seen 'em, every time, in studio shots with that circular 'pop' screen, which keeps the singer at the right distance from the mic. There are some very inexpensive ones around, so it's probably worth going for. One word of caution : They need powering, usually 'phantom' power from the recording console, or audio interface for home stuff. Make sure that your interface can, in fact, supply 'phantom power' before investing. Most of 'em can, of course, but it needs confirming. If there's no phantom power, the Shure will work, and work well, but the resulting sound will not be the most hi-fi, is all.
Hope this helps.